Large cell neuroendocrine carcinoma of the larynx: definition of an entity

Primary Small Cell Neuroendocrine Carcinoma of nasopharynx with metastatic cervical lymph nodes: an exceedingly rare entity with review of literature

Small cell neuroendocrine carcinoma of nasopharynx is extremely rare and displays aggressive nature with a poor prognosis. Neuroendocrine tumours rarely arise from the head and neck region and pose a diagnostic and management challenge. In English literature, only 16 cases of primary small cell neuroendocrine carcinoma of nasopharynx have been reported so far; and to the best of our knowledge, this is the seventeenth case and second in the younger age group. Here, we report the case of an adolescent male patient who presented with nasal blockage, repeated episodes of epistaxis and neck swellings. After proper diagnostic workup, the diagnosis of small cell neuroendocrine carcinoma of nasopharynx was made. The patient was treated with chemotherapy, followed by radiotherapy. Imaging investigation executed after the end of the treatment exhibited complete remission of the disease. The patient is kept under active surveillance with no signs of relapse at present.

Primary Surgical Management of Laryngeal Neuroendocrine Neoplasms: A Single Institution Case Series

Objective: Laryngeal neuroendocrine neoplasms (NENs) are rare diseases. A single institution retrospective study was done of the outcome of patients with laryngeal NENs who undergo primary surgery as the first treatment modality. Methods: Retrospective analysis of medical records of patients with laryngeal NENs between 2009 and 2018. Cases were classified by applying the 2022 World Health organization Classification of Head and Neck Tumors (5th edition). Results: Six patients were eligible at our tertiary center: 1 large cell neuroendocrine carcinoma (NEC), 3 small cell NEC, 1 neuroendocrine tumor grade 1, and 1 neuroendocrine tumor grade 2. All admitted patients received upfront surgeries, including 3 transoral CO2 laser surgeries and 3 total laryngectomies with or without elective neck dissection. Four patients underwent subsequent chemoradiotherapy. Although 3 patients had recurrent disease and distal metastasis, the overall survival was generally improved. Conclusion: According to our institutional experience, upfront surgery in the first-line setting of a multi-modality approach with adjuvant chemoradiotherapy plays a very important role in managing laryngeal NECs, and may confer additional survival benefit in some patients of the large cell carcinoma subgroup.

Small-Cell Carcinoma of Nasopharynx: A Case Report of Unusual Localization

Neuroendocrine tumors are a spectrum of rare and highly heterogeneous neoplasms with distinct functional and biological behavior in relation to location, tumor size, and histological differentiation. Neuroendocrine tumors arise from the neuroendocrine cells of the diffuse neuroendocrine system located in almost every organ. Neuroendocrine tumors in the head and neck district are usually reported in sinonasal cavities and larynx. We present the case of a nasopharyngeal small-cell neuroendocrine carcinoma, which, as far as we know, is the 16th case reported in literature.

Large cell neuroendocrine carcinoma originating in the subglottic larynx

Large cell neuroendocrine carcinoma (LCNEC) of the larynx is an exceedingly rare cancer of the head and neck that is difficult to diagnose. Few case reports of laryngeal LCNEC exist within the literature, and it was not until recently that LCNEC was recognized as a discrete subtype of neuroendocrine carcinoma. Given its recent recognition as a distinct subtype, histologic characteristics distinguishing LCNEC from other poorly differentiated carcinomas remain under investigation. Various reports have shown genetic alterations such as p53 and/or p16 overexpression, which are typically associated with infection by human papilloma virus (HPV). However, some reports have shown p53 and/or p16 overexpression in HPV negative samples. In this case, we discuss a 67-year-old patient with a history of extensive alcohol and tobacco use with a newly diagnosed T4N0M0, high grade, LCNEC of the subglottic larynx. Tumor pathology demonstrated positive staining for typical neuroendocrine (NE) markers like synaptophysin and chromogranin A; however, there was diffuse CK34βE12 and p16 expression. LCNEC is a newly classified subtype of poorly differentiated neuroendocrine (NE) tumors, and the diagnosis requires consideration of the clinical presentation, microscopic features, and immunostaining markers.

Update from the 5th Edition of the World Health Organization Classification of Head and Neck Tumors: Overview of the 2022 WHO Classification of Head and Neck Neuroendocrine Neoplasms

This review article provides a brief overview of the new WHO classification by adopting a question-answer model to highlight the spectrum of head and neck neuroendocrine neoplasms which includes epithelial neuroendocrine neoplasms (neuroendocrine tumors and neuroendocrine carcinomas) arising from upper aerodigestive tract and salivary glands, and special neuroendocrine neoplasms including middle ear neuroendocrine tumors (MeNET), ectopic or invasive pituitary neuroendocrine tumors (PitNET; formerly known as pituitary adenoma) and Merkel cell carcinoma as well as non-epithelial neuroendocrine neoplasms (paragangliomas). The new WHO classification follows the IARC/WHO nomenclature framework and restricts the diagnostic term of neuroendocrine carcinoma to poorly differentiated epithelial neuroendocrine neoplasms. In this classification, well-differentiated epithelial neuroendocrine neoplasms are termed as neuroendocrine tumors (NET), and are graded as G1 NET (no necrosis and < 2 mitoses per 2 mm²; Ki67 < 20%), G2 NET (necrosis or 2-10 mitoses per 2 mm², and Ki67 < 20%) and G3 NET (> 10 mitoses per 2 mm² or Ki67 > 20%, and absence of poorly differentiated cytomorphology). Neuroendocrine carcinomas (> 10 mitoses per 2 mm², Ki67 > 20%, and often associated with a Ki67 > 55%) are further subtyped based on cytomorphological characteristics as small cell and large cell neuroendocrine carcinomas. Unlike neuroendocrine carcinomas, head and neck NETs typically show no aberrant p53 expression or loss of RB reactivity. Ectopic or invasive PitNETs are subtyped using pituitary transcription factors (PIT1, TPIT, SF1, GATA3, ER-alpha), hormones and keratins (e.g., CAM5.2). The new classification emphasizes a strict correlation of morphology and immunohistochemical findings in the accurate diagnosis of neuroendocrine neoplasms. A particular emphasis on the role of biomarkers in the confirmation of the neuroendocrine nature of a neoplasm and in the distinction of various neuroendocrine neoplasms is provided by reviewing ancillary tools that are available to pathologists in the diagnostic workup of head and neck neuroendocrine neoplasms. Furthermore, the role of molecular immunohistochemistry in the diagnostic workup of head and neck paragangliomas is discussed. The unmet needs in the field of head and neck neuroendocrine neoplasms are also discussed in this article. The new WHO classification is an important step forward to ensure accurate diagnosis that will also form the basis of ongoing research in this field.

Neuroendocrine Carcinoma of the Larynx and Pharynx: A Clinical and Histopathological Study

Simple Summary

Neuroendocrine carcinomas (NECs) of the head and neck are rare. The presented series of 20 patients with laryngeal and pharyngeal NECs is population-based and one of the largest published to date. We analyzed the treatment results according to the type of therapy and the role of various standard (synaptophysin-chromogranin-CD56, Ki-67, p16, HPV, and EBV) and some novel (INSM1 and PD-L1) neuroendocrine markers or potential prognosticators. The results indicate the following: (1) laryngeal and pharyngeal NECs accounted for 0.43% and 0.17% of the cases in the corresponding tumor groups, respectively; (2) neuroendocrine differentiation can be reliably determined by INSM1 immunohistochemistry; (3) the prognosis was determined by the nodal stage and TNM stage but not by the histological grade (which refers to moderately and poorly differentiated NECs); (4) except in well-differentiated NECs and early-stage (T1-2N0-1) moderately/poorly differentiated NECs, aggressive multimodal therapy is needed; and (5) the p16, HPV, and EBV statuses failed to show any prognostic value.

Abstract

Neuroendocrine carcinomas (NECs) of the head and neck are rare and the experience scanty. The Cancer Registry of Slovenia database was used to identify cases of laryngeal and pharyngeal NECs diagnosed between 1995–2020. Biopsies were analyzed for the expression of standard neuroendocrine markers (synaptophysin, chromogranin, CD56), INSM1, Ki-67, p16, and PD-L1 (using the combined positive score, CPS). In situ hybridization for human papillomavirus (HPV) and Epstein–Barr virus (EBV) was performed. Twenty patients (larynx, 12; pharynx, 8) were identified. One tumor was well differentiated (WD), five were moderately differentiated (MD), and 14 were poorly differentiated (PD). Disease control was achieved solely by surgery in 4/4 MD/PD T1-2N0-1 tumors. Eight patients died of the disease, seven of which were due to distant metastases. All three traditional markers were positive in 11/17 NECs and the INSM1 marker in all 20 tumors. Two of fourteen p16-positive tumors were HPV-positive, but all three nasopharyngeal NECs were EBV-negative. Three tumors had CPSs ≥ 1. In conclusion, INSM1 was confirmed to be a reliable marker of neuroendocrine differentiation. Except in WD and early-stage MD/PD tumors, aggressive multimodal therapy is needed; the optimal systemic therapy remains to be determined. p16, HPV, and EBV seem to bear no prognostic information.

Neuroendocrine Neoplasms of the Larynx: A Clinicopathologic Analysis of 27 Neuroendocrine Tumors and Neuroendocrine Carcinomas

Laryngeal neuroendocrine neoplasms (NENs) are rare and heterogeneous, encompassing well-differentiated neuroendocrine tumors (NETs; grade 1, 2, and 3), neuroendocrine carcinomas (NECs, small cell and large cell types), and mixed neuroendocrine non-neuroendocrine neoplasms (MiNEN). We aimed to study the clinicopathologic spectrum of these neoplasms. A retrospective review of all primary laryngeal NENs diagnosed from 2005 to 2017 was undertaken. Mitotic index was divided into < 2, ≥ 2-10, and > 10 mitoses/2 mm², with a Ki-67 labelling index of < 2%, ≥ 2-20%, and > 20% for the NET grade 1, 2 and 3 categories, respectively. A total of 27 patients were included. The median age at presentation was 60 years; the male-to-female ratio was 8:1. Supraglottis (n = 22) was the most frequently affected subsite. There were 9 NETs grade 2 (G2), and 18 NECs cases. There were no NET grade 1 or 3 cases in our cohort. Among the NETs G2, the morphology was epithelioid (2), plasmacytoid (3), clear (2), oncocytic (1), and rhabdoid (1). Unique 'glomeruloid structures' (n = 5), calcification (n = 3), lymphoid aggregates (n = 5), intranuclear inclusions (n = 2), hyaline globules (n = 3), and Leisegang rings (n = 2) were identified. NECs comprised 16 small cell neuroendocrine carcinoma and 2 large cell neuroendocrine carcinoma. On immunohistochemistry, tumor cells expressed AE1/AE3 (86%), synaptophysin (100%), chromogranin (100%), INSM1 (100%), calcitonin (33.3%). In the NEC group, p53 aberrant expression (87.5%), Retinoblastoma (Rb) loss (88.2%), and diffuse p16 immunoreactivity (66.7%) were additionally observed. Lymph-node metastasis was detected in 62.5% and 85.7%, while distant metastasis in 55.6% and 76.9%, respectively in NET G2 and NEC. Laryngeal NENs are aggressive neoplasms with a high rate of nodal and distant metastasis. Awareness of the wide pathologic spectrum of laryngeal NENs and appropriate use of IHC is needed to render an accurate diagnosis. Ki67 assessment is strongly recommended for laryngeal NEN prognostication.

Genomics of High-Grade Neuroendocrine Neoplasms: Well-Differentiated Neuroendocrine Tumor with High-Grade Features (G3 NET) and Neuroendocrine Carcinomas (NEC) of Various Anatomic Sites

High-grade neuroendocrine neoplasms (HG-NENs) are clinically aggressive diseases, the classification of which has recently been redefined. They now include both poorly differentiated NENs (neuroendocrine carcinoma, NECs) and high proliferating well-differentiated NENs (called grade 3 neuroendocrine tumors, G3 NETs, in the digestive system). In the last decade, the "molecular revolution" that has affected all fields of medical oncology has also shed light in the understanding of HG NENs heterogeneity and has provided new diagnostic and therapeutic tools, useful in the management of these malignancies. Considering the kaleidoscopic aspects of HG NENs in various anatomical sites, this review systematically addresses the genomic landscape of such neoplasm throughout the more common thoracic and digestive locations, as well as it will consider other rare but not exceptional primary sites, including the skin, the head and neck, and the urogenital system. The revision of the available literature will then be oriented to understand the translational relevance of molecular data, by analyzing conceptual issues, clinicopathological correlations, and unmet needs in this field.

Lymphoepithelial Carcinoma of Larynx and Hypopharynx: A Rare Clinicopathological Entity

(1) Background: Lymphoepithelial carcinoma of the hypopharynx and larynx is a rare tumor with fewer than 50 cases in the published literature. We present a literature review to discuss the clinical findings, viral or genetic associations, diagnostic challenges, histopathological findings and therapeutic aspects of the disease. (2) Methods: A comprehensive literature review was performed through MEDLINE/PubMed from 1968 to 2018. We identified 21 studies comprising 46 patients. Data on all the clinicopathological features, diagnostic modalities, treatment options and viral or genetic etiology were extracted and analyzed using SPSS. (3) Results: The mean age of presentation was 64 years (range 40–82 years) and mostly involved males. The supraglottis and pyriform sinus were the most commonly involved sub-sites, with surgery as the preferred treatment modality. The presence of the Epstein–Barr virus possibly directs a viral etiology. The incidence of cervical and distant metastasis was 54% and 21%, respectively. The median survival time was 30 months. (4) Conclusions: Lymphoepithelial carcinoma of the hypopharynx is an aggressive tumor with a strong predilection for regional and distant metastasis. Surgery, in combination with adjuvant therapy, provides promising results. Immunohistochemistry helps in differentiating LEC from other pathologies.

Metastatic large cell neuroendocrine carcinoma of larynx: Individualizing tumor biology by dual tracer positron emission tomography/computed tomography (68Ga-DOTATATE and 18F-fluorodeoxyglucose) molecular imaging and disease stabilization following 177Lu-DOTATATE peptide receptor radionuclide therapy after initial progression on chemoradiotherapy

Debate exists on the disease biology and course of primary large cell neuroendocrine carcinoma (LCNEC) of larynx, being classified as a variant of atypical carcinoid by the World Health Organisation-2005 classification, while literature of its aggressive behavior indicating poorly differentiated neuroendocrine carcinoma (akin to pulmonary LCNEC) exists. The utility of dual tracer positron emission tomography/computed tomography (⁶⁸Ga-DOTATATE and ¹⁸F-fluorodeoxyglucose) in deciphering the dynamic tumor biology and feasibility of peptide receptor radionuclide therapy (PRRT) is illustrated in metastatic LCNEC of epiglottis after disease progression following conventional chemoradiotherapy. Relatively, atypical sites of soft-tissue metastases (subcutaneous tissue of arm, scrotal sac, peritoneum, and lamina of thyroid cartilage) and xiphisternum and disease stabilization following ¹⁷⁷Lu-DOTATATE PRRT were other noteworthy unique aspects of this report.

Update on Neuroendocrine Carcinomas of the Larynx

OBJECTIVES

Laryngeal neuroendocrine carcinomas are heterogeneous neoplasms characterized by neuroendocrine differentiation. Their prognoses are dependent on tumor type, therefore different classifications have been developed. Moreover, other tumors have overlapping pathologic features posing a range of diagnostic possibilities.

METHODS

A review of the literature was performed to comprehensively understand the classification and diagnosis of these tumors.

RESULTS

We review the past and present classification systems, with emphasis to the latest 2017 World Health Organization Classification of Head and Neck Tumors. We highlight salient clinicopathologic features and discuss the presumptive etiologic role of human papilloma virus. We share a practical algorithmic approach to the diagnosis of suspected neuroendocrine neoplasms of the larynx including a novel marker for neuroendocrine differentiation, insulinoma-associated protein 1.

CONCLUSIONS

Accurate diagnosis and grading of laryngeal neuroendocrine carcinomas is critical for prognostication and therapeutic decision making. The use of an algorithm is instrumental in assuring the exclusion of mimickers.

Epstein-Barr Virus-Positive Large Cell Neuroendocrine Carcinoma of the Nasopharynx: Report of One Case and Review of the Literature

Epstein-Barr Virus (EBV)-positive neuroendocrine carcinoma (NEC) of the nasopharynx is exceedingly rare, only two cases have been reported in the literature. While EBV infection is strongly associated with nasopharyngeal carcinoma, which is carcinoma with squamous differentiation, the link between EBV and NEC is not well known, and can be diagnostically challenging. In this study, we report the third case of EBV-positive large cell NEC of nasopharynx with neck lymph node metastasis. The patient was treated with combined radiation and chemotherapy and showed complete clinical and radiological response. Similar treatment response has been reported in another patient with high stage EBV-positive large cell NEC, suggesting that EBV status is an important prognostic factor. Recognition of this rare tumor is important for disease management and patient prognosis. We also review the literature about the clinical and pathologic presentation of neuroendocrine tumors of nasopharynx.

Large cell neuroendocrine carcinoma of the nasal cavity: an extremely rare and new distinct entity

Large cell neuroendocrine carcinoma (LCNEC) is a rare but distinct entity of nasal cavity carcinomas. Only a very few cases have been reported in the nasal cavity. Its treatment is not well established. We report the case of a LCNEC in a 70 years old patient who presented with right nasal obstruction and epistaxis since 2 months. Diagnosis was confirmed by histological and immunohistochemical study. The patient underwent complete endoscopic removal of the tumor combined to adjuvant chemoradiotherapy. After 6 month follow-up, the patient was in complete clinical and radiological remission. We will discuss in this paper the various epidemiology, clinical features, pathological findings, differential diagnosis, and evolution of treatment of this uncommon malignancy in the light of current knowledge. Optimal treatment strategies are yet to be determined for this rare malignancy with poor prognosis including surgery and chemoradiotherapy.

P53 Gene Mutation Identified by Next Generation Sequencing in Poorly Differentiated Neuroendocrine Carcinoma of the Nasal Cavity

Neuroendocrine carcinomas (NECs) are epithelial neoplasms showing morphologic, immunophenotypic or ultrastructural evidence of neuroendocrine differentiation. The 2017 WHO Classification of Head and Neck Tumours classifies NECs into well, moderately and poorly differentiated NECs according to light microscopic features, mitotic rate and presence of tumour necrosis. In this study, we performed next generation sequencing (NGS) using a targeted 161 cancer gene panel on a poorly differentiated NEC of the nasal cavity. The tumour was composed of large cells arranged in poorly formed glands and solid nests. The mitotic count rate was 30/10 HPFs and p53 protein was strongly expressed in all tumour cells. NGS identified a missense mutation, c.764T > G (p.Ile255Ser) in the TP53 gene with an allele frequency of 85%. This mutation results in an isoleucine to serine substitution and a non-functional protein. No other mutations were identified. These results suggest that TP53 mutations may drive oncogenesis in poorly differentiated NECs of the head and neck.

Neuroendocrine Carcinomas of the Larynx and Head and Neck: Challenges in Classification and Grading

Primary neuroendocrine carcinomas (NECs) of the larynx and head and neck are an uncommon and heterogeneous group of neoplasms categorized by the 2017 WHO Classification of Head and Neck Tumors as: (a) well-differentiated (WD-NEC), (b) moderately-differentiated (MD-NEC), and (c) poorly-differentiated (PD-NEC) with small cell and large cell types. The classification incorporates elements of differentiation and grading and closely correlates to the 5-year disease specific survival of 100, 52.8, 19.3 and 15.3% for each diagnostic category. These survival rates are based on historical data limited by the previous lack of standard pathologic diagnostic criteria. The classification has de-emphasized the use of the terms "carcinoid" and "atypical carcinoid" as diagnostic categories. The adoption of uniform pathologic criteria for the classification of NECs of the head and neck should enable the design of high quality studies in order to understand the molecular alterations of these neoplasms.

Differential Diagnosis in Neuroendocrine Neoplasms of the Larynx

The differential diagnosis of neuroendocrine neoplasms of the larynx is broad and includes lesions of epithelial, mesenchymal, and neuroectodermal origin. These lesions have overlapping clinical and pathologic aspects and must be carefully considered in the differential diagnosis of laryngeal neoplasms. The prognosis and treatment are also different among these tumor types, which necessitates making these distinctions clinically. The current literature was reviewed to provide updated information regarding the epithelial-derived tumors, including carcinoid, atypical carcinoid, small cell neuroendocrine carcinomas, large cell neuroendocrine carcinoma, and squamous cell carcinoma with neuroendocrine component. These tumors are compared and contrasted with non-epithelial-derived tumors such as paraganglioma and nonmucosal tumors, such as medullary thyroid carcinoma. The morphologic and cytologic features are discussed, along with helpful immunohistochemical and ancillary investigations.

Update from the 4th Edition of the World Health Organization Classification of Head and Neck Tumours: What is New in the 2017 WHO Blue Book for Tumours of the Hypopharynx, Larynx, Trachea and Parapharyngeal Space

Chapter 3 "Tumours of the hypopharynx, larynx, trachea, and parapharyngeal space" of the World Health Organization (WHO) Blue Book 2017 "Classification of Head and Neck Tumours" shows a shortened list of entities, especially due to reducing the number of benign and malignant soft tissue tumours, malignant melanoma and some others, which are transferred to more frequently affected regions of the head and neck. The basic concept of the new edition is to assimilate all advances concerning the discussed tumours in a shorter framework, appropriate for daily work. The main emphasis is on the most frequent lesions and tumors originating from the covering squamous epithelium. Laryngeal and hypopharyngeal conventional squamous cell carcinoma (CSCC), its variants and precursor lesions, occupy a major part of the chapter. New data on etiopathogenesis, with the focus on human papillomavirus (HPV) infection, are discussed in relation to the entities of the squamous epithelium. Although only a small fraction of these lesions are HPV-related, further studies are required for evaluation of the potential prognostic and therapeutic benefit of mRNA HPV determination. In contrast to earlier data, laryngeal and hypopharyngeal verrucous SCC, spindle cell SCC and basaloid SCC are not anymore considered as HPV-related tumours. New data on the pathogenesis of spindle cell SCC exhibiting divergent differentiation by epithelial-mesenchymal transition, are also briefly discussed. The most important innovation is brought by the section on precursor lesions, in which a unified two-tier classification, consisting of low- and high-grade dysplasia, is introduced. The proposed two-tier system can also be transformed into a three-tier classification for treatment purposes, with a distinction between carcinoma in situ and high-grade dysplasia. The reviewed morphological criteria of the proposed system are based on the amended Ljubljana classification. The section on laryngeal neuroendocrine carcinomas (NEC) represents a considerable improvement in terminology and classification. NEC are divided into well-, moderate- and poorly-differentiated neuroendocrine carcinoma. The latter is additionally divided into small cell NEC and large cell NEC (LCNEC). It is of extreme importance that LCNEC, which was associated in the WHO 2005 edition with atypical carcinoid/moderately differentiated neuroendocrine carcinoma, grade II, has now been transferred into the group of poorly differentiated NEC, grade III, displaying a specific morphology and poorer prognosis.

Large Cell Neuroendocrine Carcinoma of the Head and Neck: A Clinicopathologic Series of 10 Cases With an Emphasis on HPV Status

Large cell neuroendocrine carcinoma (LCNEC) is a high-grade neuroendocrine neoplasm first described in the lung and subsequently well documented in many other anatomic sites. It has only recently been recognized that LCNEC can also occasionally arise in the head and neck. The role of human papillomavirus (HPV), which is associated with some small cell carcinomas of the head and neck, has not been investigated for LCNEC. We sought to further characterize the histologic, immunophenotypic, and clinical features of LCNEC and also investigate the role of HPV in this newly described group of tumors. The surgical pathology archives of 2 large academic institutions were searched for cases of LCNEC arising in the head and neck. p16 immunohistochemistry and HPV in situ hybridization were performed, and clinical information was obtained from electronic medical records. Ten cases of head and neck LCNEC were identified. The tumors arose in 6 men and 4 women ranging in age from 14 to 70 years (median, 63.5 y). The primary tumor sites were the oropharynx (n=4), the sinonasal tract (n=3), and the larynx (n=3). The LCNECs consisted of nests and trabeculae of medium-large cells with abundant cytoplasm, coarse chromatin, and prominent nucleoli with very high mitotic rates. The tumor nests were often associated with necrosis, peripheral palisading, and rosette formations. The LCNECs were positive for pan-cytokeratin and at least 1 neuroendocrine marker (most often synaptophysin) and were largely negative for p63 (focal staining in 2/10) and CK5/6 (staining in 1/10). The LCNECs demonstrated aggressive clinical behavior: 8 of 10 presented with advanced disease, 5 of 10 died, with 4 more living but with persistent tumor. Three of 10 LCNECs were HPV-related (HPV-LCNEC); they arose in the oropharynx (n=2) and sinonasal tract (n=1). The HPV-LCNECs did not differ from the HPV-negative tumors in histologic appearance or behavior: 2 patients with HPV-LCNEC have died because of their disease and 1 remains alive but with widespread metastases. LCNEC is a rare but distinct form of head and neck carcinoma that exhibits aggressive clinical behavior. A subset of oropharyngeal and sinonasal LCNEC is HPV related, but the presence of HPV may not impart a more favorable prognosis. Because of its aggressive behavior, LCNEC should be distinguished from moderately differentiated neuroendocrine carcinoma and squamous cell carcinoma. The morphology of LCNEC overlaps considerably with the nonkeratinizing appearance of HPV-related squamous cell carcinoma, and as a result a high index of suspicion is needed to identify LCNEC. Immunohistochemical studies for synaptophysin and p63 are helpful tools for making this distinction.

p16 overexpression in high-grade neuroendocrine carcinomas of the head and neck: potential diagnostic pitfall with HPV-related carcinomas

High-grade neuroendocrine carcinomas (HGNECs) of the head and neck have the morphological appearance of undifferentiated carcinomas and could be histologically similar to human papillomavirus (HPV)-associated non-keratinizing squamous cell carcinomas of the head and neck. The aim of the study is to characterize histologically, immunohistochemically, and virologically these unusual neoplasms. Nineteen HGNECs of the head and neck (1 oropharyngeal, 5 sinonasal, 7 of the larynx, and 6 of the parotid gland) were reviewed and analyzed with a immunohistochemical panel, with special emphasis on cell cycle proteins. The tumors were tested for HPV by in situ hybridization (GenPoint HPV, Dako) and PCR (SPF10-DEIA-LiPA25). Merkel cell polyomavirus was studied using the antibody CM2B4. Fifteen HGNEC were of small cell and 4 of large cell type. Most of the tumors (14/19, 73.7 %), including all the pure small cell carcinomas, showed a strong and diffuse positive staining for p16. Eleven of them (78.5 %) had Rb loss and a low or absent cyclin D1 expression. All cases were negative for HPV and polyomavirus. Most patients were smokers, diagnosed at advanced stages of the disease, and had a poor outcome, with a 5-year survival of 18 %. In conclusion, HGNECs of the head and neck are infrequently related to HPV infection, but usually show strong, diffuse positive p16 immunostaining due to Rb pathway dysregulation. Awareness of this immunohistochemical pattern of expression may avoid a potential diagnostic pitfall with HPV-associated non-keratinizing squamous cell carcinomas, which have a better prognosis.

Neuroendocrine tumours in rare sites: differences in nomenclature and diagnostics-a rare and ubiquitous histotype

The diagnosis of neuroendocrine tumours in typical sites, as gastrointestinal tract and lung, is based upon well-coded criteria that have become familiar to most of the pathologists. Much more difficult is the recognition and allocation of proper nomenclature to be referred to the same histotype in locations where these tumours have a lower incidence. The aim of our review was to provide a quick handbook of the main diagnostic pitfalls known in literature that can interpose in the histopathological examination of neuroendocrine tumours in rare sites (urinary system and male genital organs, female genital organs, head and neck and breast).

Hypopharyngeal large cell neuroendocrine carcinoma

Neuroendocrine carcinoma (NEC) of the head and neck is rare. We report a case of a 56-year-old man with a 6-week history of dysphagia, a neck mass and weight loss. He was diagnosed with a hypopharyngeal large cell NEC (LCNEC) with metastases to multiple sites. He received two cycles of cisplatin and etoposide. Subsequent restaging scan revealed progressive disease. The patient declined further chemotherapy and died shortly after. This is the third case of LCNEC of hypopharynx reported in the English literature and the first to progress on platinum-based chemotherapy. Although LCNEC of the head and neck is still classified as an atypical carcinoid, there is increasing evidence it is a distinct clinicohistopathological entity that carries an especially poor prognosis. Currently, there is a paucity of data to guide treatment of this rare malignancy.

[A Case of Oropharyngeal Large Cell Neuroendocrine Carcinoma]

The large cell neuroendocrine carcinoma (LCNEC) of the lung was first reported in detail by Travis et al. in 1991. Extrapulmonary LCNEC rarely occurs, and only 22 cases have been reported in the head and neck mucosal regions. Today LCNEC of the larynx is contained in the moderately differentiated/Grade 2 category. However some authors advocate that LCNEC of the larynx should be separated from this category because of the difference in the clinical manifestations and pathological features. Standard treatment for head and neck mucosal LCNEC (M-LCNEC) has not been confirmed. However we suggested the efficacy of postoperative chemotherapy for M-LCNEC. This report describes a case of an LCNEC of the oropharynx. The patient was a 64-year-old man. We treated him with surgery and chemoradiotherapy. He has been disease-free for 36 months after adjuvant-chemotherapy.

High-Grade Neuroendocrine Carcinoma of the Larynx

Objective:

To report a single institutional series of high-grade neuroendocrine carcinoma of the larynx (NCL), a very rare yet aggressive tumor. To review the management of NCL, including discussion of clinical behavior, treatment outcome, and prognosis.

Method:

A retrospective chart review of high-grade laryngeal neuroendocrine carcinomas at a single institution, including small- and large-cell neuroendocrine carcinomas. A total of 8 patients with high-grade NCL treated at our institution from 1992 to 2014 were identified.

Results:

The median age at diagnosis was 65.5 years (range, 43-80). Five patients were male. Two patients had a known smoking history. Primary tumor location was supraglottic in 7 patients and glottic in 1 patient. Primary treatment consisted of surgery alone (3 patients), radiotherapy alone (1 patient), combination of chemotherapy and radiotherapy (1 patient), and surgery followed by postoperative chemoradiotherapy (3 patients). Locoregional recurrence followed by distant metastasis occurred in 6 patients. Median overall survival was 44.0 months (95% CI, 3-62.0).

Conclusion:

High-grade NCL is a rare diagnosis. Compared to well- and moderately differentiated NCL, high-grade NCL has a far more aggressive clinical course and associated with a worse prognosis. To our knowledge, this is the largest series of patients with high-grade NCL treated at a single institution. Prompt diagnosis and multimodality therapy including elective neck dissection may improve survival.

Laryngeal Neuroendocrine Carcinomas: A Retrospective Study of 14 Cases

Laryngeal neuroendocrine carcinomas (LNECs) are rare and highly heterogeneous which present a wide spectrum of pathological and clinical manifestations. Fourteen patients with histologically demonstrated LNEC were collected and analyzed retrospectively. The 14 cases were classified into 3 subtypes: typical carcinoid in 2, atypical carcinoid in 5, and small cell neuroendocrine carcinoma in 7. The mean survival time of the 14 patients in this study was 112.5 months (95% CI, 81.5–143.6). Surgeries were performed for 2 patients of typical carcinoid, and they were alive with no evidence of recurrence after 24 and 47 months of follow-ups. Patients in the atypical carcinoid group were treated with surgeries and postoperative radiotherapy. After 58.4 months of follow-ups (range: 9–144), 2 patients showed no evidence of disease and 1 was lost to follow-up after 72 months. The other 2 patients died of other unrelated diseases. In the small cell neuroendocrine carcinoma group, a combination of chemotherapy and radiotherapy was applied. The mean survival time was 79.7 months (95% CI, 37.9–121.4), and the 5-year survival rate was 53.6%. In conclusion, the clinical behaviors, treatment protocols, and prognosis are different for each subtype of LNECs.

[Epithelial neuroendocrine tumors of the upper respiratory tract: New entities, new perspectives]

Epithelial neuroendocrine tumors of the upper respiratory tract are rare and are classified as typical and atypical carcinoid versus small cell neuroendocrine carcinoma. Furthermore, a giant cell variant of neuroendocrine carcinoma is suggested corresponding to the bronchopulmonary system as well as a recently described subtype of oropharyngeal small cell neuroendocrine carcinoma associated with human papillomavirus. Many arguments relying on clinical as well as on molecular findings indicate that the distinction between carcinoid and poorly differentiated neuroendocrine carcinoma does not only reflect different degrees of differentiation of otherwise related tumors but indicates the existence of substantially different types of neoplasms.

Clinical recommendations on the treatment of neuroendocrine carcinoma of the larynx: A meta-analysis of 436 reported cases

BACKGROUND

Current recommendations on the treatment of neuroendocrine carcinoma of the larynx (NCL) are based on anecdotal evidence. With this meta-analysis, our purpose was to provide clinicians with more substantiated guidelines in order to improve the treatment outcome of the patients affected with NCL.

METHODS

A structured literature search for all research concerning NCL was performed against the MEDLINE and EMBASE databases. Available data was normalized, pooled, and statistically analyzed.

RESULTS

Four hundred thirty-six cases of NCL were extracted from 182 studies, of which 23 were typical carcinoid, 163 were atypical carcinoid, 183 were small-cell neuroendocrine carcinoma, 29 were large-cell neuroendocrine carcinoma, and 38 were unspecified carcinoid tumors. The 5-year disease-specific survival (DSS) was 100% for typical carcinoid, 53% for atypical carcinoid, 19% for small-cell neuroendocrine carcinoma, and 15% for large-cell neuroendocrine carcinoma (p < .001). Patients with an atypical carcinoid treated with surgery had better DSS than those treated with radiotherapy (60% vs 54%; p = .035). Postoperative radiotherapy did not result in better DSS in atypical carcinoid. Patients with an atypical carcinoid, not undergoing surgical treatment of the neck, developed isolated regional recurrence in 30% of cases (p = .001). Radiochemotherapy yielded the best DSS for small-cell neuroendocrine carcinoma compared to other modalities (31% vs 13%; p = .001).

CONCLUSION

Typical carcinoid can be treated by local excision alone. Atypical carcinoids do not seem to respond well to radiotherapy and are best managed through radical surgical excision in combination with elective neck dissection. Patients with small-cell neuroendocrine carcinoma or large-cell neuroendocrine carcinoma seem to benefit most from chemoradiotherapy.

[Large cell neuroendocrine carcinoma of the nasopharynx: A case report]

Neuroendocrine carcinoma of the head and neck is a rare entity. The parotid gland is the most commonly affected site. A nasopharyngeal site has not been previously described. We report a 35-year-old patient who consulted for tinnitus and nasal obstruction. The assessment found a nasopharyngeal tumour T4N0M0. The patient underwent 6 cycles of chemotherapy based on VP16 and cisplatin, followed by radiotherapy at a dose of 70 Gy to the nasopharynx and 50 Gy to the neck. The evolution was marked by clinical improvement and radiological stability. Six months after the end of treatment, the patient had a local and meningeal relapse. He received palliative care. He died 19 months after the end of treatment.

Neuroendocrine neoplasms of the head and neck: some suggestions for the new WHO classification of head and neck tumors

As knowledge and understanding in pathology evolve, classifications and nomenclature also change to reflect those advances. The 2005 World Health Organization Classification of Head and Neck Tumours was a significant step towards diagnostic standardization of head and neck neuroendocrine carcinomas; however, in the last 10 years there have been new data supporting the recognition of "large cell neuroendocrine carcinoma" as a distinctive high grade carcinoma in the head and neck, a lesion not included in the 2005 Classification. In addition, the terms "middle ear adenoma" and "carcinoid tumor of middle ear" are still widely used to describe a neoplasm that is neither a pure adenoma nor a carcinoid tumor but a lesion with variable mixed exocrine and endocrine differentiation. Largely using the diagnostic criteria of the WHO classification of neuroendocrine carcinomas of the lung, we propose the terms "neuroendocrine carcinoma, grade 1"; "neuroendocrine carcinoma, grade 2"; "neuroendocrine carcinoma, grade 3, large cell type"; and "neuroendocrine carcinoma, grade 3, small cell type" for the classification of neuroendocrine carcinomas of the head and neck in a future WHO classification. In addition, we also proposed the term "mixed epithelial neuroendocrine tumor" of the middle ear as an alternative for "middle ear adenoma" and "carcinoid tumor of the middle ear".

Carcinosarcoma ex non-recurrent pleomorphic adenoma composed of TTF-1 positive large cell neuroendocrine carcinoma and myofibrosarcoma: apropos a rare Case

We present a carcinosarcoma ex non-recurrent pleomorphic adenoma composed of a large cell neuroendocrine carcinomatous component and a spindle cell sarcoma with myofibroblastic differentiation. The tumor contained a hyalinized transition zone where the classical PA appeared to acquire two different histopathological patterns of malignant transformation of the epithelial component. The carcinomatous component was strongly and diffusely positive for low-molecular weight cytokeratins (AE1-3), synaptophysin, thyroid transcription factor-1 and focally positive for chromogranin A. All these markers were negative in the sarcomatous component. The sarcomatous component displayed immunoreactivity for smooth muscle actin with a predominantly linear, subplasmalemmal pattern. No expression of CD31, S100 protein, h-caldesmon, desmin, CD34, p63, myogenin, Myo D1 and c-kit was detected. Strong immunohistochemical expression of p53 was documented in both the carcinomatous and sarcomatous components as well as in the atypical epithelial component in the transition zone associated with the hyalinized pleomorphic adenoma.

Mucosal large cell neuroendocrine carcinoma of the head and neck regions in Japanese patients: a distinct clinicopathological entity

Backgrounds

Large cell neuroendocrine carcinoma (LCNEC) is well-known as a lung cancer subtype. This study assessed the prevalence of head and neck mucosal LCNEC (M-LCNEC).

Methods

M-LCNEC was studied clinically, histologically and immunohistochemically.

Results

Of 814 surgically resected cases of mucosal head and neck carcinoma, only eight cases (0.98%; all men, mean age 64.6 years) were rediagnosed as M-LCNEC. They occurred in the oropharynx (n=3), larynx (n=4) and hypopharynx (n=1). Seven of the cases had regional lymph node metastases and four resulted in death. Histologically, M-LCNEC had a sheet-like trabacular organoid growth pattern of relatively large basaloid cells in which central necrosis, rosette formation, peripheral palisading and high mitotic figures were evident. M-LCNEC was immunopositive for two or three neuroendocrine markers (CD56, chromogranin-A and synaptophysin). All cases showed high proliferative activity.

Conclusion

M-LCNEC in the head and neck regions is a distinct histopathological entity whose positivity for neuroendocrine markers makes its diagnosis important. As about half of the patients died of the disease, M-LCNEC has a relatively poor prognosis.

Is human papillomavirus involved in laryngeal neuroendocrine carcinoma?

The purpose of this study was to detect human papillomavirus (HPV) infection in laryngeal neuroendocrine carcinoma (LNEC) and to explore the possible relationship between HPV-induced malignant transformation and prognosis in LNEC. Ten cases of LNEC from a tertiary referral hospital were retrospectively analyzed. Clinical data were subtracted from patients’ files. Pretreatment biopsy material was tested for the presence of HPV6, 11, 16, and 18 using a PCR-based detection method. Immunohistochemical staining was performed for Ki-67, p16^INK4A, and p53 expression. All cases were negative for the low-risk HPV types HPV6 and HPV11 that are associated with laryngeal papillomatosis. High-risk HPV was detected in two cases; an atypical carcinoid was positive for HPV16 and a large-cell neuroendocrine carcinoma for HPV18. Both HPV-positive tumors had a high Ki-67 labeling index. Two of the four cases with a good response to therapy were hrHPV-positive (both HPV DNA positive) compared with none of the five poor responders. Our findings show that HPV may play a role in the pathogenesis of LNEC. The relationship between HPV, improved prognosis and good response to therapy for squamous cell carcinoma of the head and neck may also be true for a subset of LNEC.

Head and neck large cell neuroendocrine carcinoma should be separated from atypical carcinoid on the basis of different clinical features, overall survival, and pathogenesis

According to the 2005 World Health Organization classification of head and neck tumors, neuroendocrine tumors can be subdivided into typical carcinoid, atypical carcinoid, and small cell carcinoma. Similar tumors diagnosed as large cell neuroendocrine carcinomas (LCNECs) in the lung are diagnosed as atypical carcinoids in the head and neck region. We studied neuroendocrine tumors and analyzed whether LCNEC should be separated from atypical carcinoid in the head and neck region. Twenty-three cases of primary head and neck neuroendocrine tumors were included and subdivided into typical carcinoid, atypical carcinoid, and small cell carcinoma according to the 2005 World Health Organization guidelines, and then LCNECs were separated from atypical carcinoids according to modified criteria using the Ki-67-labeling index and mitotic count. Clinical information and survival data were obtained, and immunohistochemical studies for p53 were conducted. The 5-year survival rates for the 2 typical carcinoids, 7 atypical carcinoids, 7 LCNECs, and 7 small cell carcinomas were 100.0%, 83.3%, 21.4%, and 20.8%, respectively (P=0.032). The LCNEC patients were older (mean age, 61 vs. 41 y; P=0.038), more commonly in advanced stage (stages III and IV 100% vs. 28.6%, P=0.01), with a poorer prognosis (5-year survival 21.4% vs. 83.3%, P=0.03), and more commonly had tumors overexpressing p53 (85.7% vs. 0%, P=0.005) as compared with atypical carcinoid patients. LCNECs should be separated from atypical carcinoids as a new entity of neuroendocrine carcinoma in the head and neck region. The new classification may provide better risk stratification and useful information for proper treatment.

Large cell neuroendocrine carcinoma of the head and neck

Large cell neuroendocrine carcinoma is a poorly differentiated neuroendocrine carcinoma that usually occurs in the lung. Although rare in the head and neck, salivary and mucosal subtypes are recognized. This article describes their characteristic light microscopic and immunohistochemical features and highlights the importance of accurate diagnosis, management and prognostic implications.

Terminology and classification of neuroendocrine neoplasms of the larynx

OBJECTIVES

To review the history and literature on neuroendocrine neoplasms of the larynx and discuss the terminology and classification of these tumors.

STUDY DESIGN

Contemporary review.

METHODS

Published journal articles identified through PubMed and conference proceedings were reviewed.

RESULTS

Neuroendocrine neoplasms of the larynx include both epithelial (carcinomas) and neural-type lesions (paragangliomas).The nomenclature of these tumors has changed quite a bit over time, but recently, clearer categories have emerged that are biologically meaningful. They can overlap clinically and histologically so that segregation into the clinically relevant subtypes can be difficult, but it is extremely important to do so as they have a wide range of behaviors going from benign to rapidly fatal.

CONCLUSIONS

Neuroendocrine neoplasms of the larynx can be clearly categorized into the five tumor types: typical carcinoid, atypical carcinoid, small cell neuroendocrine carcinoma, large cell neuroendocrine carcinoma, and paraganglioma. These have concrete biologic and clinical significance and clearly dictate patient treatment.